about, the flu is on the rise. In a big way in much of the country. The number of states with high flu activity more than tripling from 6 to 20 last week. Here to talk about it is abc news chief health and medical editor rich besser. Tell us what is going on. Flu tends to start in the southeast and spread. It went from 6 to 20 states in a week. What type of flu? This is the same strain that we saw in 2009 with the pandemic. The h1n1 strain. That's included in the current vaccine. The bad news is that tends to hit healthy children and adults more than some of the other flu strains. Are we going to have a serious flu season? It's a little early to know that. I would take precautions. It's not too late to get vaccinated. Not too late to practice good hand washing. Do fist bumps instead of hand shakes. I would imagine the temperatures and the fluctuation in the temperatures can't help. Low humidity, flu viruses stay in the air more. We crowd together. All the travel. Thank you, rich. Good to see you in the new year. Now, the big game is tonight that we were talking about.

This transcript has been automatically generated and may not be 100% accurate.

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